Phosphonyl- and thiophosphonyl-thio-nylamines and process of preparing



United States Patent 3,179,6$8 PHOSPHONYL- AND THEQKHOSPHONYL-THIO-NYLAMINES AND PROCESS OF PREPARING Ludwig Maier, Zurich, Switzerland,assignor to Monsanto Company, a corporation of Delaware No Drawing.Filed June 20, 1962, Ser. No. 203,697 4 Claims. (Cl. 260-461) It hasbeen found that a novel class of phosphorus compounds having the generalformula can be prepared by reaction of phosphites with amidothionylhalide.

In this formula R and R are identical or different, possibly substitutedand/or unsaturated aliphatic, cycloaliphatic, araliphatic, aromatic orheterocyclic radicals which may be linked together, and R and R areidentical or different hydrocarbon radicals which may be linkedtogether. A is sulfur or oxygen. For insecticidal use preferredcompounds are those in which R R R and R each have not more than 18carbon atoms, more preferably not more than 8 carbon atoms, andespecially alkyl radicals of not more than 8 carbon atoms.

The phosphites serving as first reactants of the general formula arewell known from the literature. Examples are: dimethyl-, diethyl-,di-n-propyl-, di-iso-propyl, di-n-butyl, di-iso-butyl-, di-iso-amyl-,di-n-heptyl-, di-n-octy1-, di-Z- octyl, dibenzyl-, dicyclohexyl-,diphenyl-phosphite, etc. Examples of known phosphites with R /Rconnected together are: ethylenephosphite, propylene-1,3-phosphite,propylene-1,2-phosphite, tetrahydrofurylene 3,4 phosphite, etc.Unsymmetrically substituted phosphites which contain a combination ofthe simple radicals enumerated above are as Well suited as alsodiphosphites of which, for example H0P(OCH CH O) POH is well known.Moreover, the phosphites may possess optional substituents, as long asthese do not hinder the reaction of invention. As substituents qualify,for example, halogen,

ether, ester, cyano, nitro groups, etc.

Thiophosphites or bis-thiophosphites of the formulae /P SH and HS P R 0OCHZCHZO P S H OCHZCHZO di-n-propylamine, di-iso-propylamine,dibutylamine, N-

ice

. methylbenzylamine, d-ibenzylamine, ethylaniline, diphenprocess ofinvention, has been described in the German patent application1,046,034; however, since another processing method has been usedtherein, the resulting end-products are notthiophosphonyl-thionylamines, but thionophosphoric acid esters of theformula The reaction leading to the phosphonylorthiophosphonyl-thionylamines of invention is base-d on the reaction ofphosphites or thiophosphites with an amidothionyl halide in the presenceof an acid-binding agent, such as triethylamine, cyclohexyldiethylamine,alpha-picoline, etc., and especially in the form of an alkali salt.

Conveniently, the acid halide is gradually added to a solution of thealkali phosphite or alkali thiophosphite in anhydrous benzene andheated, if necessary, for some time. The reaction occurs with, forexample, sodium diethylphosphite and dimethylamidosulfinic acid chlorideaccording to the following equation:

The phosphonyland thiophosphonyl-thionylamines which have not yet beenknown until now, are valuable pesticides, especially insecticides. Theyare also intermediates, since they can be oxidized in conventionalmanner to the corresponding phosphonyland thiophosphonylsulfonylamines.

EXAMPLE 1 Preparation of To 16.1 g. (0.1 mole) of sodiumdiethylphosphite in 50 ml. of benzene is slowly added a solution of 13g. (0.1 mole) of dimethylamidosulfinic acid chloride in 20 m1. ofbenzene. The reaction is exothermic. The reaction mixture issubsequently refluxed for 2 hours and tractionally distilled.

Yield 9.6 g. (=42% of the theory); B.P. 59-63 C./0.05 mm.; 11 1.4273.

What is claimed is:

1. A process for preparing compounds of the formula wherein R R R and Rare alkyl having not more than 8 carbon atoms, A is selected from theclass consisting of oxygen and sulfur, comprising reacting in thepresence of an acid-binding agent a phosphite of the formula R 0(R2O)PAH wherein R R and A are as defined hereinabove with anamidosulfinic halide of the formula R R NSOX wherein R and R are asdefined hereinabove, and X is a halogen atom. Q

2. A process of claim 1 wherein the phosphite is re acted in the form ofan alkali metal salt in an inert solvent.

. 1 I V 6a 3. A process of claim 1 wherein X is the chlorine atom-2,891,059 6/59 Malz et a1 260-461 4. A process of preparing 2,893,9107/59 Birurn et a1. 260461 :fi (0 0 1.1 3,044,981 7/62 B/IEIIZ 6; a1260--461 0 0 5 FOREIGN PATENTS comprising reacting in an inert solventsodium dicthyl- 1,353,950 5 Germany phosphite withdimethylarnidosulfinic acid chloride. 1 21 922 59 Frane Refemmes Cited ythe 3 CHARLES E. PARKER, Primary Examiner.

UNITED STATES PATENTS 10 M. HERMAN, IRVING MARUS, Examiners;

2,811,543 10/ 57 Coover et a1. 260-461

1. A PROCESS FOR PREPARING COMPOUNDS OF THE FORMULA